Check it, if your employer has one. See if you've waived any right to be personally (not your property) searched.
Unless you're in a super-sensitive position, you probably didn't waive anything.
Which means the instant they laid hands on you, they likely committed a battery.
Might go check with HR about company policy on physical searches, and what constitutes an unlawful/nonconsensual touching. Also ask them about company policy on reporting such matters (the MWAG report), what sort of documentation security must make on such things, what reports they must write after an encounter with a "suspected" employee, and your entitlement to copies of any such report. You probably don't have much of a leg to stand on, since it's the private sector, but you might well be able to file a complaint of your own and see where it takes you.
Someone's out to get you, and/or they're looking for a reason to remove you from your position for cost savings or reorganization purposes.
Evaluate how secure you are in your position, and whether you want to be released, before proceeding.